package Demo2;

public class Computer {
    public void powerOn() {
        System.out.println("打开电脑");
    }

    public void poweroff() {
        System.out.println("关闭电脑");
    }

    public void useService(USB usb) {
        usb.openDevices();
        if (usb instanceof Mouse) {
            Mouse mouse = (Mouse) usb;
            mouse.Click();
        } else if (usb instanceof KeyBoard) {
            KeyBoard keyBoard = (KeyBoard) usb;
            keyBoard.input();
        }
        usb.closeDevices();
    }
}
